The present invention relates to an extension device for telephone, more particularly to a device capable of connecting to a digital telephone to achieve data exchange, storage and editing, and providing other functions of easy input and convenient carrying-around.
Telephones have been an important communication media of the modem life. Some telephone networks already provide the functions of combining caller's phone number into transmission for the answerer to receive it via a certain detector, or even to store it for reference or further to use it for automatic dialing. These have significantly increased the convenience of telephone use. But people may still be unsatisfied with these relatively simple functions of provided by a traditional digital telephone which are limited to answering, calling, electric notebook for recording phone numbers and names, and reviewing incoming messages only.
To summarize the convenience of telephone use, it is practical for number input since the keyboard of traditional telephone is of CCITT standard keyboard, but very inconvenient and slow for text input (such as for a person's name, characters should be replaced by number combination which is bothersome to operate). Furthermore, since a telephone set is usually fixed at a certain location in the room, sometimes it will be inaccessible for the user to reach the information of phone number or name if he or she is far away from the telephone. Similarly, when the user obtains a new phone number or other relative information outdoors, he or she has to write it down or memorize it by any other way before further registering it to the digital telephone. Therefore, the duplicated process is quite inconvenient.
European Patent No. 0 450 550 A2 discloses a communication apparatus capable of connecting to an information media, such as an electronic notebook, an IC card or the like. The apparatus is a telephone exchange device which can link itself in a common ISDN (Integrated Services Digital Networks) or an analog network through an office line interface card, and connect to some extension phones through extension interface cards, providing functions of identifying telephone calls, storing messages, exchanging information with some specific extension phones or storage media installed to the extension phones, and speed dialing.
Further, European Patent No. 0 452 629 A2 discloses a telephone apparatus similar to the previously mentioned apparatus of European Patent No. 0 450 550 A2. It is still a telephone exchange apparatus working with extension telephones and provides a function of reception control in accordance with an input schedule.
Though the apparatuses of prior arts as disclosed in the aforesaid patents provide functions of storing information on media (such as electronic notebook, IC card or the like), performing data exchange, speed dialing and schedule control, they all require a specific telephone exchange apparatus connecting them to extension telephones. In other words, users cannot use those information storage media (electronic notebook, IC card or the like) directly on a common digital telephone, and a common digital telephone cannot perform the aforesaid functions by itself.